Dual-active bridge converter and applications of same

Abstract

A dual-active bridge (DAB) converter is provided. The DAB converter comprises a primary sub-circuit coupled to a direct-current (DC) input voltage, a first secondary sub-circuit and a second secondary sub-circuit, and a transformer isolating the primary sub-circuit from the first and the second secondary sub-circuits and comprising a predetermined number of turns. Each of the first and the secondary sub-circuits comprise a corresponding inductor; the first and the second secondary sub-circuits being configurable in a series mode and a parallel mode by switching configurations of a first, second and third transition switch; and the first and the second secondary sub-circuits providing an output charging voltage and an output charging current for charging an external device. A charging station comprising one or more charging poles, with each charging pole comprising one of more DAB converters is also disclosed.

We claim: 
     
         1 . A dual-active bridge (DAB) converter, comprising:
 a primary sub-circuit coupled to a direct-current (DC) input voltage;   a first secondary sub-circuit and a second secondary sub-circuit;   a transformer isolating the primary sub-circuit from the first and the second secondary sub-circuits, and comprising a predetermined number of turns;   each of the first and the secondary sub-circuits comprising a corresponding inductor;   the first and the second secondary sub-circuits being configurable in a series mode and a parallel mode by switching configurations of a first, second and third transition switch; and   the first and the second secondary sub-circuits providing an output charging voltage and an output charging current for charging an external device.   
     
     
         2 . The DAB converter of  claim 1 , wherein the primary sub-circuit consists of four bridge switches, and a primary winding having a corresponding primary winding voltage and primary current. 
     
     
         3 . The DAB converter of  claim 2 , further comprising a capacitor bank in parallel to the combination of the four bridge switches. 
     
     
         4 . The DAB converter of  claim 1 , wherein each of the first and second secondary sub-circuits comprise four bridge switches, a corresponding secondary winding having a corresponding secondary winding voltage and secondary current. 
     
     
         5 . The DAB converter of  claim 4 , wherein each of the first and second secondary sub-circuits further comprise a capacitor bank in parallel to the combination of the corresponding four bridge switches. 
     
     
         6 . The DAB converter of  claim 1 , wherein in the series mode, the first and the second secondary sub-circuits are connected in series and generate a higher output charging voltage than the parallel mode configuration. 
     
     
         7 . The DAB converter of  claim 1 , wherein in the parallel mode, the first and the second secondary sub-circuits are connected in parallel and generate a lower output charging voltage than the series mode configuration. 
     
     
         8 . The DAB converter of  claim 1 , wherein the output charging voltage ranges from about 200V to 1000V. 
     
     
         9 . A charging station comprising:
 at least one charging pole;   each charging pole comprising at least one dual-active bridge (DAB) converter module, each DAB converter module comprising:
 a primary sub-circuit coupled to a direct-current (DC) input voltage; 
 a first secondary sub-circuit and a second secondary sub-circuit; 
 a transformer isolating the primary sub-circuit from the first and the second secondary sub-circuits, and comprising a predetermined number of turns; 
 each of the first and the secondary sub-circuits comprising a corresponding inductor; 
 the first and the second secondary sub-circuits being configurable in a series mode and a parallel mode by switching configurations of a first, second and third transition switch; and 
 the first and the second secondary sub-circuits providing an output charging voltage and an output charging current for charging an external device; 
   wherein one or more electric vehicles are charged based on the output charging voltage of the corresponding DAB converter.   
     
     
         10 . The charging station of  claim 9 , wherein one or more DAB converters of each charging pole are arranged in parallel to provide fast charging power to one or more electric vehicles. 
     
     
         11 . The charging station of  claim 9 , wherein the primary sub-circuit of each DAB converter module consists of four bridge switches, and a primary winding having a corresponding primary winding voltage and primary current. 
     
     
         12 . The charging station of  claim 9 , wherein each DAB converter module further comprises a capacitor bank in parallel to the combination of the four bridge switches. 
     
     
         13 . The charging station of  claim 9 , wherein each of the first and second secondary sub-circuits of each DAB converter module comprise four bridge switches, a corresponding secondary winding having a corresponding secondary winding voltage and secondary current. 
     
     
         14 . The charging station of  claim 9 , wherein each of the first and second secondary sub-circuits of each DAB converter module further comprise a capacitor bank in parallel to the combination of the corresponding four bridge switches. 
     
     
         15 . The charging station of  claim 9 , wherein in the series mode, the first and the second secondary sub-circuits of each DAB converter module are connected in series and generate a higher output charging voltage than the parallel mode configuration. 
     
     
         16 . The charging station of  claim 9 , wherein in the parallel mode, the first and the second secondary sub-circuits of each DAB converter module are connected in parallel and generate a lower output charging voltage than the series mode configuration. 
     
     
         17 . The charging station of  claim 9 , wherein the output charging voltage ranges from about 200V to 1000V.